Walls built to permanently retain or support adjoining earth or rock shall be constructed of approved masonry, plain or reinforced concrete.  Corbeled retaining walls constructed of dry solid concrete, stone, or other material, may be permitted if approved by the Superintendent of Building and Zoning Inspection.
   Unless provision is made to drain off water, a hydrostatic pressure due to a head equal to the height of the wall shall be assumed.
   The pressure on the soil under such retaining walls shall not exceed the safe bearing capacities allowed by this Building and Housing Code.
   Retaining walls shall be properly protected by a durable coping unless such walls are constructed of concrete.
   A separate permit is required for retaining walls over three feet in height.
(Ord. 42-1981.  Passed 2-23-81.)